Files
Unexpected-Keyboard/srcs/compose/compile.py
Jules Aguillon 4a429357ef compose: Fix parsing of long sequences from json files
Sequences longer than two characters were not read correctly from json
files, creating conflicts and causing dropped sequences.

The detection of collision in sequences is also improved. Two colliding
sequences are removed.
2024-12-19 00:34:24 +01:00

294 lines
10 KiB
Python

import textwrap, sys, re, string, json, os
from array import array
# Compile compose sequences from Xorg's format or from JSON files into an
# efficient state machine.
# See [ComposeKey.java] for the interpreter.
#
# Takes input files as arguments and generate a Java file.
# The initial state for each input is generated as a constant named after the
# input file.
# Parse symbol names from keysymdef.h. Many compose sequences in
# en_US_UTF_8_Compose.pre reference theses. For example, all the sequences on
# the Greek, Cyrillic and Hebrew scripts need these symbols.
def parse_keysymdef_h(fname):
with open(fname, "r") as inp:
keysym_re = re.compile(r'^#define XK_(\S+)\s+\S+\s*/\*.U\+([0-9a-fA-F]+)\s')
for line in inp:
m = re.match(keysym_re, line)
if m != None:
yield (m.group(1), chr(int(m.group(2), 16)))
dropped_sequences = 0
# Parse XKB's Compose.pre files
def parse_sequences_file_xkb(fname, xkb_char_extra_names):
# Parse a line of the form:
# <Multi_key> <minus> <space> : "~" asciitilde # TILDE
# Sequences not starting with <Multi_key> are ignored.
line_re = re.compile(r'^((?:\s*<[^>]+>)+)\s*:\s*"((?:[^"\\]+|\\.)+)"\s*(\S+)?\s*(?:#.+)?$')
char_re = re.compile(r'\s*<(?:U([a-fA-F0-9]{4,6})|([^>]+))>')
def parse_seq_line(line):
global dropped_sequences
prefix = "<Multi_key>"
if not line.startswith(prefix):
return None
m = re.match(line_re, line[len(prefix):])
if m == None:
return None
def_ = m.group(1)
try:
def_ = parse_seq_chars(def_)
result = parse_seq_result(m.group(2))
except Exception as e:
# print(str(e) + ". Sequence dropped: " + line.strip(), file=sys.stderr)
dropped_sequences += 1
return None
return def_, result
char_names = { **xkb_char_extra_names }
# Interpret character names of the form "U0000" or using [char_names].
def parse_seq_char(sc):
uchar, named_char = sc
if uchar != "":
c = chr(int(uchar, 16))
elif len(named_char) == 1:
c = named_char
else:
if not named_char in char_names:
raise Exception("Unknown char: " + named_char)
c = char_names[named_char]
# The state machine can't represent sequence characters that do not fit
# in a 16-bit char.
if len(c) > 1 or ord(c[0]) > 65535:
raise Exception("Char out of range: " + r)
return c
# Interpret the left hand side of a sequence.
def parse_seq_chars(def_):
return list(map(parse_seq_char, re.findall(char_re, def_)))
# Interpret the result of a sequence, as outputed by [line_re].
def parse_seq_result(r):
if len(r) == 2 and r[0] == '\\':
return r[1]
return r
# Populate [char_names] with the information present in the file.
with open(fname, "r") as inp:
for line in inp:
m = re.match(line_re, line)
if m == None or m.group(3) == None:
continue
try:
char_names[m.group(3)] = parse_seq_result(m.group(2))
except Exception:
pass
# Parse the sequences
with open(fname, "r") as inp:
seqs = []
for line in inp:
s = parse_seq_line(line)
if s != None:
seqs.append(s)
return seqs
# Basic support for comments in json files. Reads a file
def strip_cstyle_comments(inp):
def strip_line(line):
i = line.find("//")
return line[:i] + "\n" if i >= 0 else line
return "".join(map(strip_line, inp))
# Parse from a json file containing a dictionary sequence → result string.
def parse_sequences_file_json(fname):
def tree_to_seqs(tree, prefix):
for c, r in tree.items():
if isinstance(r, str):
yield prefix + [c], r
else:
yield from tree_to_seqs(r, prefix + [c])
try:
with open(fname, "r") as inp:
tree = json.loads(strip_cstyle_comments(inp))
return list(tree_to_seqs(tree, []))
except Exception as e:
print("Failed parsing '%s': %s" % (fname, str(e)), file=sys.stderr)
# Format of the sequences file is determined by its extension
def parse_sequences_file(fname, xkb_char_extra_names={}):
if fname.endswith(".pre"):
return parse_sequences_file_xkb(fname, xkb_char_extra_names)
if fname.endswith(".json"):
return parse_sequences_file_json(fname)
raise Exception(fname + ": Unsupported format")
# A sequence directory can contain several sequence files as well as
# 'keysymdef.h'.
def parse_sequences_dir(dname):
compose_files = []
xkb_char_extra_names = {}
# Parse keysymdef.h first if present
for fbasename in os.listdir(dname):
fname = os.path.join(dname, fbasename)
if fbasename == "keysymdef.h":
xkb_char_extra_names = dict(parse_keysymdef_h(fname))
else:
compose_files.append(fname)
sequences = []
for fname in compose_files:
sequences.extend(parse_sequences_file(fname, xkb_char_extra_names))
return sequences
# Turn a list of sequences into a trie.
def add_sequences_to_trie(seqs, trie):
global dropped_sequences
def add_seq_to_trie(seq, result):
t_ = trie
for c in seq[:-1]:
t_ = t_.setdefault(c, {})
if isinstance(t_, str):
return False
c = seq[-1]
if c in t_:
return False
t_[c] = result
return True
def existing_sequence_to_str(seq): # Used in error message
i = 0
t_ = trie
while i < len(seq):
if seq[i] not in t_: break # No collision ?
t_ = t_[seq[i]]
i += 1
if isinstance(t_, str): break
return "".join(seq[:i]) + " = " + str(t_)
for seq, result in seqs:
if not add_seq_to_trie(seq, result):
dropped_sequences += 1
print("Sequence collide: '%s' and '%s = %s'" % (
existing_sequence_to_str(seq),
"".join(seq), result), file=sys.stderr)
# Compile the trie into a state machine.
def make_automata(tries):
previous_leafs = {} # Deduplicate leafs
states = []
def add_tree(t):
this_node_index = len(states)
# Index and size of the new node
i = len(states)
s = len(t.keys())
# Add node header
states.append(("\0", s + 1))
i += 1
# Reserve space for the current node in both arrays
for c in range(s):
states.append((None, None))
# Add nested nodes and fill the current node
for c in sorted(t.keys()):
states[i] = (c, add_node(t[c]))
i += 1
return this_node_index
def add_leaf(c):
if c in previous_leafs:
return previous_leafs[c]
this_node_index = len(states)
previous_leafs[c] = this_node_index
# There are two encoding for leafs: character final state for 15-bit
# characters and string final state for the rest.
if len(c) > 1 or ord(c[0]) > 32767: # String final state
javachars = array('H', c.encode("UTF-16-LE"))
states.append((-1, len(javachars) + 1))
for c in javachars:
states.append((c, 0))
else: # Character final state
states.append((c, 1))
return this_node_index
def add_node(n):
if type(n) == str:
return add_leaf(n)
else:
return add_tree(n)
states.append((1, 1)) # Add an empty state at the beginning.
entry_states = { n: add_tree(root) for n, root in tries.items() }
return entry_states, states
# Debug
def print_automata(automata):
i = 0
for (s, e) in automata:
s = "%#06x" % s if isinstance(s, int) else '"%s"' % str(s)
print("%3d %8s %d" % (i, s, e), file=sys.stderr)
i += 1
def batched(ar, n):
i = 0
while i + n < len(ar):
yield ar[i:i+n]
i += n
if i < len(ar):
yield ar[i:]
# Print the state machine compiled by make_automata into java code that can be
# used by [ComposeKeyData.java].
def gen_java(entry_states, machine):
chars_map = {
# These characters cannot be used in unicode form as Java's parser
# unescape unicode sequences before parsing.
-1: "\\uFFFF",
"\"": "\\\"",
"\\": "\\\\",
"\n": "\\n",
"\r": "\\r",
ord("\""): "\\\"",
ord("\\"): "\\\\",
ord("\n"): "\\n",
ord("\r"): "\\r",
}
def char_repr(c):
if c in chars_map:
return chars_map[c]
if type(c) == int: # The edges array contains ints
return "\\u%04x" % c
if c in string.printable:
return c
return "\\u%04x" % ord(c)
def gen_array(array):
chars = list(map(char_repr, array))
return "\" +\n \"".join(map(lambda b: "".join(b), batched(chars, 72)))
def gen_entry_state(s):
name, state = s
return " public static final int %s = %d;" % (name, state)
print("""package juloo.keyboard2;
/** This file is generated, see [srcs/compose/compile.py]. */
public final class ComposeKeyData
{
public static final char[] states =
("%s").toCharArray();
public static final char[] edges =
("%s").toCharArray();
%s
}""" % (
# Break the edges array every few characters using string concatenation.
gen_array(map(lambda s: s[0], machine)),
gen_array(map(lambda s: s[1], machine)),
"\n".join(map(gen_entry_state, entry_states.items())),
))
total_sequences = 0
tries = {} # Orderred dict
for fname in sorted(sys.argv[1:]):
tname, _ = os.path.splitext(os.path.basename(fname))
if os.path.isdir(fname):
sequences = parse_sequences_dir(fname)
else:
sequences = parse_sequences_file(fname)
add_sequences_to_trie(sequences, tries.setdefault(tname, {}))
total_sequences += len(sequences)
entry_states, automata = make_automata(tries)
gen_java(entry_states, automata)
print("Compiled %d sequences into %d states. Dropped %d sequences." % (total_sequences, len(automata), dropped_sequences), file=sys.stderr)
# print_automata(automata)